I'll say this...after owning the airflo one for a year now, I wouldn't buy another system again. First, for NE Saltwater; I fish either deep or intermediate. Thats all. I never need to kinda get down. Its all or nothing in this game from my perspective. So the middle sink rate line and the floating line never get used. The fast sink doesn't sink fast enough for my liking either, not enough meat to pull the floating rear down with it.
Secondly, I have found its just much easier to change spools and restring the rod. With these things you need to swap the line and then hand spool the whole thing back up into its little pouch; otherwise it comes out in knots the next time. The line casts fine and doesn't hinge on the connection point, it just doesn't seem to work as well at being an intermediate and a fast sink line.
I agree with ssully whole heartedly; only wish I knew this when I bought the line. I was trying to save a few bucks on a spare spool when in retrospect, I should have just bought one.